jquery和struts的用户注册 用户名验证

	<script type="text/javascript">

	

	 	function check(){

			var username = $("#username").val();

			$("#result").text("正在检测用户名是否可用");

			var url="Login/login_validate.action";

			$.post(url,{name:username},function(data){

					$("#result").text(data);

					$("#result").css("color","red");

			},"text");

		}

	</script>

  </head>

  

  <body>

	<form action="Login/login_input.action" method="post">

		Username:<input type="text" id="username" name="user.username"/>

				 <input type="button" value="Check!" onclick="check();">

				 <div id="result"></div>

		Password:<input type="password" id="password" name="user.password"/><br/>

		<input type="submit" value="Submit"/>

	</form>

  </body>

</html>

public class UserLoginAction extends ActionSupport{

	/**

	 * 

	 */

	private static final long serialVersionUID = 1L;

	

	private User user;

	

	public void validateUsername(){

		String name = ServletActionContext.getRequest().getParameter("name");

		this.getUser().setUsername(name);

		PrintWriter pw = null;

		try {

			pw = ServletActionContext.getResponse().getWriter();

			if(user.getUsername().equals("111")){

				pw.write("已存在");

			}else if(user.getUsername().equals("123")){

				pw.write("可以使用");

			}else{

				pw.write("不可以使用");

			}

		} catch (IOException e) {

			e.printStackTrace();

		} finally{

			pw.flush();

			pw.close();

		}

	}